Latest generation wireless communications systems include distributed antenna systems (DAS), distributed direct current (DC) radio systems, remote radio heads (RRH), 4G and long term evolution (LTE) cellular communication systems. These communications systems now commonly locate radios next to antennas on towers outside of communications shelters. Active Antenna Systems also may use similar installation configurations where the antennas and the radios are one unit.
The radios are located outside of the communications shelter on top of the tower and are therefore more susceptible to damage from lighting strikes and other electrical power surge events. Individual power lines run to each individual radio also increasing the amount of power cabling exposed to power surge events. Thus, DC power plants and telecommunication equipment at communication stations with distributed power have more risk of damage due to direct lighting strikes and power surges.